Electric power tool

Abstract

An electric power tool includes a tool portion, a fuel cell, a power drive source, and a water-holding unit. The water-holding unit holds a reaction water produced in the fuel cell by oxidation reaction between a fuel and an oxidizing agent.

1 . An electric power tool comprising:
 a tool portion;   a fuel cell that generates electric power by oxidation reaction between a fuel and an oxidizing agent;   a power drive source that receives electric power to drive the tool portion; and   a water-holding unit that holds a reaction water produced in the fuel cell by the oxidation reaction.   
     
     
         2 . The electric power tool according to  claim 1 , further comprising:
 a holder portion that detachably holds the water-holding unit.   
     
     
         3 . The electric power tool according to  claim 1 , wherein
 the water-holding unit includes:
 a drainage inlet to which the reaction water flows in, and 
   the electric power tool includes:
 a drainage outlet from which the reaction water is discharged; and 
 a positioner that positions the drainage inlet with respect to the drainage outlet, so that the reaction water flows in from the drainage outlet to the drainage inlet. 
   
     
     
         4 . The electric power tool according to  claim 3 , wherein
 a packing is provided around at least one of the drainage outlet and the drainage inlet, and   the positioner is configured to position the drainage inlet with respect to the drainage outlet along such a direction in which the packing is inhibited from being damaged.   
     
     
         5 . The electric power tool according to  claim 3 , wherein
 the drainage outlet is provided in a section where the water-holding unit is held.   
     
     
         6 . The electric power tool according to  claim 3 , further comprising:
 an operation prohibiting unit that prohibits operation of the power drive source, when the drainage inlet is not located at a position where the reaction water can flow in from the drainage outlet to the drainage inlet.   
     
     
         7 . The electric power tool according to  claim 6 , wherein
 the operation prohibiting unit is configured to prohibit the operation of the power drive source by interrupting a supply passage of electric power from the fuel cell to the power drive source.   
     
     
         8 . The electric power tool according to  claim 1 , further comprising:
 a reaction water remover that removes the reaction water held in the water-holding unit from the water-holding unit.   
     
     
         9 . The electric power tool according to  claim 8 , wherein
 the reaction water remover includes a reaction water outlet formed in the water-holding unit in order to discharge the reaction water held in the water-holding unit out of the water-holding unit.   
     
     
         10 . The electric power tool according to  claim 8 , further comprising:
 a fan that is driven by the power drive source,   wherein the reaction water remover is configured to pass at least part of an air flow induced by the fan through an interior of the water-holding unit.   
     
     
         11 . The electric power tool according to  claim 2 , further comprising:
 a fuel tank that stores a fuel to be supplied to the fuel cell,   wherein the fuel tank and the water-holding unit are integrally formed.   
     
     
         12 . The electric power tool according to  claim 1 , further comprising:
 a main body portion that includes the tool portion and the power drive source,   wherein the water-holding unit is separately provided from the main body portion.   
     
     
         13 . The electric power tool according to  claim 12 , wherein
 the water-holding unit is configured to be attachable to a user of the electric power tool.   
     
     
         14 . The electric power tool according to  claim 1 , wherein
 the water-holding unit includes:
 a drainage inlet to which the reaction water flows in, and 
 a back flow inhibiting unit that inhibits the reaction water held in the water-holding unit from flowing backward from the drainage inlet out of the water-holding unit. 
   
     
     
         15 . The electric power tool according to  claim 1 , wherein
 the water-holding unit includes an absorber that absorbs and holds the reaction water.